Electrical circuits

How do you find the Norton equivalent? I_norton

-Short the load resistor to get the current Isc=In -Use ohms law, KCL or superposition to get the current Isc.

How do you find the thevenin equivalent? Vth

1) After finding Rth: -Put voltage sources back -Keep Rload out 2) Find Voc (Voc = Va - Vb) -Apply KVL to get Voc

How do you find the thevenin equivalent? Rth

1) Remove the load resistor 2) Short the voltage sources or Open the current sources 3) Find Rth

What does ICE mean?

Current Leads Voltage in an Capacitive circuit by 90 degrees.

Batteries provide power, resistors do what to power?

Dissipate or Absorb

How do you find the Norton equivalent? Rth

Find Rth same as Thevein

What terminal direction determines if a voltage source absorbs power?

If current flows in to the voltage source's + terminal...then the voltage source absorbs power

What terminal direction determines if a voltage source delivers power?

If current flows out of the voltage source's + terminal...then the voltage source delivers power.

Is the phase angle positive or negative in a lagging circuit?

Negative, and the phase angle difference is negative and the current reaches its peak AFTER the voltage.

What do you do to current sources using superposition theorem?

Open all current sources

What are capacitors in steady state or DC?

Open circuits (Coc)

Is the phase angle positive or negative in a leading circuit?

Positive, and the phase angle difference is positive and the current reaches its peak BEFORE the voltage.

What do you do to voltage sources using superposition theorem?

Short all voltage sources

What are inductors in steady state or DC?

Short circuits (Lsc)

What is the resonant frequency?

The frequency at which the circuit becomes purely resistive W0 or Fo.

What is the power factor at resonant?

The power factor is equal to one. The reactance (X) is equal to zero or XL = XC.

Superposition theorem, how do you treat each source element?

Turn on one source at a time

What does ELI mean?

Voltage Leads Current in an Inductive circuit by 90 degrees. Using the voltage as reference: "The current lags behind the voltage by 90 degrees"

Are the input voltage and current in phase in a "resonant circuit?"

Yes, therefore the phase angle is zero.